Algiers: German Chancellor Angela Merkel postponed a visit to Algeria because President Abdelaziz Bouteflika is suffering from acute bronchitis, state news agency APS said, quoting a statement from the presidency.
Merkel was due to arrive in Algeria on Monday as part of a trip to North Africa. "The visit will be reprogrammed at a date that is suitable for the two parties," the presidency said.
In Berlin, a German government spokesman confirmed Merkel had postponed the two-day trip at Algeria's request. Bouteflika, who suffered a stroke in 2013, is now rarely seen in public, mostly appearing in a state media images of meetings with visiting dignitaries.
The president, 79, has visited hospital in Europe several times since his 2013 illness, which left him hospitalised in France for months.
The veteran of Algeria's independence war has governed the North African OPEC state for more than 15 years.
Since the stroke, his state of health and medical checkups have spurred debate about whether he will finish his term and who will replace him.
He was re-elected in 2014 after a campaign where he was only seen when he came out to vote in a wheelchair.
New presidential elections are not due until 2019, but Bouteflika's opponents have called for an early ballot because of his frailty.
Government officials and his supporters say he is in charge and able to rule the country.
Algeria is a major gas supplier to Europe and after coming through its own war against armed extremists in the 1990s has become a key partner in the Western campaign against extremist militancy in the Sahel and other parts of Africa.